The economic vitality of the United States is threatened by its dependency on foreign oil from which fossil fuels and other petroleum products are generated. This situation is seen as economically and politically unfavorable because it places the United States in a position of dependency and in competition with other nations over declining resources. Moreover, reliance on fossil fuels comes at severe costs to the environment both by its raw production and burning. For example, catastrophic oil spills could conceivably eliminate entire ecosystems which would devastate food chains in which the United States and other countries rely upon. In addition, carbon dioxide emissions generated by the burning of fossil fuel is considered a driving factor of worldwide global warming which could render arable lands into deserts as weather patterns change and draughts become more common worldwide.
To address the many serious issues associated with fossil fuels, biofuels are being investigated which could aid in the replacement of conventional fossil fuels and decrease the reliance of the United States on foreign oil supplies and also reduce carbon dioxide emissions by sequestering this greenhouse gas in biomass which could be used as animal feed and/or for other environmentally sound purposes. Moreover, the production of microalgae does not require high quality or large land areas like most terrestrial crops; microalgae may be grown in arid environments and many species are capable of growth in saline waters. Accordingly, to effectively utilize the microalgae as a source of biofuel, a cost-effective process for the extraction of lipid compounds is needed. The ideal extraction process would be scalable, safe, inexpensive, and have a low energy requirement. This means minimizing the number and complexity of process steps, limiting the use of hazardous materials and minimizing the material and energy consumption for the processing of the biofuels.